'I've never felt this close to another human being, ever," she gushed of her husband-to-be. "People say we're co-dependent but we just want to be together all the time."

Osbourne and Mosshart, a vegan chef, met at supermodel Kate Moss' 2011 wedding. Osbourne says her engagement ring is extra special because the design of the bauble originates from a tender moment between her and her dad, rocker Ozzy Osbourne.

"I designed it to look like an earring that my father wore," she explains. "I used to hold my finger up to his ear when I was little and say, 'I want a ring like that.' Now I have one!"